Sinkhole in Oregon
A sinkhole in Oregon is known as a swallet or doline, is a natural hole in the Earth’s surface caused by karst processes—an example, the chemical dissolution of carbonate rocks or suffosion processes in the sandstone. Sinkholes may vary in size from 1 to 600 metres (3.3 to 2,000 ft) both in depth and diameter, and vary in form from bedrock-edged chasms to soil-lined bowls. Sinkholes may be formed gradually or suddenly, and are located worldwide. What is a sinkhole is a many faceted question with a lot of answers!
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